Lesson 2
Headers, Delimiters, and Rows
Read the table shape before converting: header rows, comma, tab, semicolon, and pipe delimiters.
Before converting CSV, confirm the table shape.
Headers
When the first row contains names, CSV can become an array of JSON objects:
id,name
1,Ada
2,Grace
[
{ "id": "1", "name": "Ada" },
{ "id": "2", "name": "Grace" }
]
Without headers, the safest JSON shape is an array of arrays or generated column names. Generated names are useful for debugging, but they are rarely a final API contract.
Delimiters
Not every tabular text file uses commas:
- Comma: common CSV
- Tab: TSV exports
- Semicolon: common in some spreadsheet locales
- Pipe: logs and internal exports
Auto-detection is useful, but when the file is small or ambiguous, choose the delimiter manually.
Row consistency
Each data row should have the expected number of fields. If the header has five columns and one row has six values, something is probably broken: a missing quote, a bad delimiter, or a pasted fragment.
Key takeaway
Headers define object keys, delimiters define field boundaries, and row consistency protects you from silent data loss.
Use the CSV Converter table preview to verify the shape before copying output.